ABSTRACT
Background: The allele frequency of the multidrug resistance 1 (MDR1) gene C3435T polymorphism differs with different ethnic populations, such as Asian, African, and Caucasian. This polymorphism has been reported to be associated with the increase of gastric cancer. Objectives: The objective of this study was to find out the association of gastric cancer incidence with MDR1 gene polymorphism in an ethnic Iranian population. Materials and Methods: In this study, 48 gastric cancer patients were diagnosed. Genomic DNA was extracted by a salting-out method. The MDR1 polymorphism was studied by a polymerase chain reaction (PCR)-restriction fragment length polymorphism method, using a standard method. Results: The polymorphic homozygote (T/T) genotype showed significantly an association with the incidence of gastric cancer compared with controls (P < 0.05). Conclusions: This study suggests that C3435T polymorphism of the MDR1 gene may be associated with gastric cancer in an ethnic Iranian population.